Answer:
Explaining a source's information in your own words helps your listeners understand your topic because if you use a detailed explanation, and use the information given correctly, you can recreate information learned in your own creative words. Using your own words gives your speech, or text, a personal touch, and makes the audience more intrigued while listening. Adding to that, using your own detailed explanation of a topic makes it clear that you really undrstood that topic, and can reproduce the material you have learned.
Hope this helps!